Field of Disclosure
The described embodiments generally relate to interoperability of discovery and coupling protocols for client devices, and more specifically, to facilitate client device interoperability in establishing video sessions with a first screen device.
Description of the Related Art
There are a number of protocols (e.g., simple service discovery protocol based discovery and launch (“DIAL”), multicast domain name system based CAST V2 API (“CAST”), etc.) that are used for discovery and/or launch of an application on a first device (e.g., television) via an application on a second device (e.g., laptop). CAST is a non-published protocol underlying some communications for ANDROID and/or GOOGLE devices. The user of the application implementing the protocol specification may, for example, cause the content being displayed by a browser on a laptop to also be displayed via an application on a television. Several problems exist with displaying content using these protocols, including device duplication and protocol interoperability problems.
Device duplication is a problem where a discovered device is listed multiple times on the discovering device as an available display device. In some instances, a device supports multiple protocols for establishing a video session with the discovering device. In these cases, the device could be presented to the user via each path through which the device is discovered—and possibly with different names. For example, an application on a laptop could use DIAL discovery to discover a television and then DIAL to launch an application on the television. But the television could also support another discovery protocol (e.g., CAST) and/or have been previously manually paired with the laptop. A manual pairing occurs when, for example, a user enters a passcode provided by the television to the laptop, or vice versa, which results in the laptop being wirelessly coupled the television via a BLUETOOTH connection. In this example, without additional steps some the television will be shown to the user three times—and possibly under different names. This situation is confusing, affects user experience, and may result in the selection of a sub-optimal protocol.
Protocol interoperability is another problem that occurs, specifically in the context of a device attempting to join an existing session between two other devices. The underlying cause for this problem is that a session started using a particular protocol cannot be joined using another protocol, and on some devices discovery modules function independently. Attempting to join an existing session using a different protocol can fail or cause the disruption of the current session and a creation of a new session. For example, a television may support both DIAL and CAST protocols, device A may support only DIAL, and device B may support both DIAL and CAST. Device A creates a session with the television using the DIAL protocol, and at some later time device B attempts to join the session using CAST—resulting in disruption of the session. The disruption is caused because the session with the television cannot operate in both DIAL and CAST at the same time.